Dr. Richard R. Querel Profile

Dr. Richard R. Querel

Atmospheric Scientist at NIWA

SPIE Involvement:

Author

Publications (10)

Proceedings Article | 15 July 2016 Paper

Through thick and thin: quantitative classification of photometric observing conditions on Paranal

Florian Kerber, Richard Querel, Bianca Neureiter, Reinhard Hanuschik

Proceedings Volume 9910, 99101S (2016) https://doi.org/10.1117/12.2232333

KEYWORDS: Clouds, Radiometry, Clouds, Radiometry, Observatories, Diagnostics, Infrared cameras, Transparency, Photometry, Stars, Cameras, Calibration

Read Abstract +

Proceedings Article | 6 August 2014 Paper

Quantifying photometric observing conditions on Paranal using an IR camera

Florian Kerber, Richard Querel, Reinhard Hanuschik

Proceedings Volume 9149, 91490M (2014) https://doi.org/10.1117/12.2055168

KEYWORDS: Clouds, Infrared cameras, Radiometry, Cameras, Observatories, Calibration, Photometry, Transparency, Stars, Atmospheric physics

Read Abstract +

Proceedings Article | 28 July 2014 Paper

All-sky homogeneity of precipitable water vapour over Paranal

Richard Querel, Florian Kerber

Proceedings Volume 9147, 914792 (2014) https://doi.org/10.1117/12.2055500

KEYWORDS: Radiometry, Astronomy, Observatories, Humidity, Microwave radiation, Statistical analysis, Infrared radiation, Atmospheric modeling, Profiling, Clouds

Read Abstract +

A Low Humidity and Temperature Profiling (LHATPRO) microwave radiometer, manufactured by Radiometer Physics GmbH (RPG), is used to monitor sky conditions over ESO’s Paranal observatory in support of VLT science operations. The unit measures several channels across the strong water vapour emission line at 183 GHz, necessary for resolving the low levels of precipitable water vapour (PWV) that are prevalent on Paranal (median ~2.4 mm). The instrument consists of a humidity profiler (183-191 GHz), a temperature profiler (51-58 GHz), and an infrared camera (~10 μm) for cloud detection. We present, for the first time, a statistical analysis of the homogeneity of all-sky PWV using 21 months of periodic (every 6 hours) all-sky scans from the radiometer. These data provide unique insight into the spatial and temporal variation of atmospheric conditions relevant for astronomical observations, particularly in the infrared. We find the PWV over Paranal to be remarkably homogeneous across the sky down to 27.5° elevation with a median variation of 0.32 mm (peak to valley) or 0.07 mm (rms). The homogeneity is a function of the absolute PWV but the relative variation is fairly constant at 10-15% (peak to valley) and 3% (rms). Such variations will not be a significant issue for analysis of astronomical data. Users at ESO can specify PWV – measured at zenith – as an ambient constraint in service mode to enable, for instance, very demanding observations in the infrared that can only be conducted during periods of very good atmospheric transmission and hence low PWV. We conclude that in general it will not be necessary to add another observing constraint for PWV homogeneity to ensure integrity of observations. For demanding observations requiring very low PWV, where the relative variation is higher, the optimum support could be provided by observing with the LHATPRO in the same line-of-sight simultaneously. Such a mode of operations has already been tested but will have to be justified in terms of scientific gain before implementation can be considered. This will be explored further in the future.

Proceedings Article | 24 September 2012 Paper

A water vapour monitor at Paranal Observatory

Florian Kerber, Thomas Rose, Arlette Chacón, Omar Cuevas, Harald Czekala, Reinhard Hanuschik, Yazan Momany, Julio Navarrete, Richard Querel, Alain Smette, Mario van den Ancker, Michel Cure, David Naylor

Proceedings Volume 8446, 84463N (2012) https://doi.org/10.1117/12.924340

KEYWORDS: Radiometry, Observatories, Humidity, Clouds, Atmospheric sciences, Calibration, Receivers, Infrared radiation, Profiling, Temperature metrology

Read Abstract +

Proceedings Article | 24 September 2012 Paper

Tools for DIY site-testing

Federico Flores, Roberto Rondanelli, Accel Abarca, Marcos Diaz, Richard Querel

Proceedings Volume 8446, 84464B (2012) https://doi.org/10.1117/12.927251

KEYWORDS: Sensors, Humidity, Unmanned aerial vehicles, Environmental sensing, Calibration, Receivers, Global Positioning System, Clouds, Atmospheric sciences, Atmospheric sensing

Read Abstract +

Proceedings Article | 7 August 2010 Paper

Support for site testing of the European Extremely Large Telescope: precipitable water vapor over La Silla

Richard Querel, Florian Kerber, Gaspare Lo Curto, Joanna Thomas-Osip, Gabriel Prieto, Arlette Chacón, Omar Cuevas, Diana Pozo, Julio Marín, David Naylor, Michel Curé, Marc Sarazin, Carlos Guirao, Gerardo Avila

Proceedings Volume 7733, 773349 (2010) https://doi.org/10.1117/12.856480

KEYWORDS: Lanthanum, Observatories, Atmospheric modeling, Satellites, Telescopes, Radiometry, Spectroscopy, Space telescopes, Atmospheric optics, Infrared spectroscopy

Read Abstract +

Proceedings Article | 7 August 2010 Paper

Giant Magellan Telescope site testing: PWV statistics and calibration

Joanna Thomas-Osip, Gabriel Prieto, Andrew McWilliam, Mark Phillips, Patrick McCarthy, Matt Johns, Richard Querel, David Naylor

Proceedings Volume 7733, 77334N (2010) https://doi.org/10.1117/12.857982

KEYWORDS: Calibration, Lanthanum, Liquid crystal on silicon, Telescopes, Atmospheric modeling, Mid-IR, Astronomy, Observatories, Astronomical telescopes, Infrared radiation

Read Abstract +

Proceedings Article | 7 August 2010 Paper

Measuring and forecasting of PWV above La Silla, APEX, and Paranal Observatories

A. Chacón, O. Cuevas, D. Pozo, J. Marín, A. Oyanadel, C. Dougnac, L. Cortes, L. Illanes, M. Caneo, M. Curé, M. Sarazin, F. Kerber, A. Smette, D. Rabanus, R. Querel, G. Tompkins

Proceedings Volume 7733, 77334K (2010) https://doi.org/10.1117/12.857542

KEYWORDS: Observatories, Atmospheric modeling, Data modeling, Lanthanum, Error analysis, Meteorology, Satellites, Humidity, Astronomy, Satellite imaging

Read Abstract +

Proceedings Article | 5 August 2010 Paper

Support for site testing of the European Extremely Large Telescope: precipitable water vapor over Paranal

Florian Kerber, Richard Querel, Reinhard Hanuschik, Arlette Chacón, Marta Caneo, Lissette Cortes, Michel Cure, Lizett Illanes, David Naylor, Alain Smette, Marc Sarazin, David Rabanus, Gregory Tompkins

Proceedings Volume 7733, 77331M (2010) https://doi.org/10.1117/12.856390

KEYWORDS: Observatories, Atmospheric modeling, Satellites, Lanthanum, Radiometry, Earth's atmosphere, Infrared telescopes, Astronomy, Spectroscopy, Data modeling

Read Abstract +

In support of characterization of potential sites for the European Extremely Large Telescope (E-ELT) the European Southern Observatory (ESO), the Institute for Space Imaging Science (ISIS) and the astrometeorology group of the Universidad Valparaiso have jointly established an improved understanding of atmospheric precipitable water vapour (PWV) above ESO's La Silla Paranal Observatory. In a first step, 8 years worth of high resolution near-IR spectra taken with VLT-UVES have been statistically analysed to reconstruct the PWV history above Paranal. To this end a radiative transfer model of Earth's atmosphere (BTRAM) developed by ISIS has been used. A median PWV of 2.1 mm is found for Paranal based on UVES data covering the period 2001-2008. Furthermore we conclude that Paranal can serve as a reference site for Northern Chile due to the stable atmospheric conditions in the region. The median offset between Paranal and Armazones is derived to be 0.3 mm, but local arbitrary variations of a few tenths of a mm between the sites have been found by measurement. In order to better understand the systematics involved two dedicated campaigns were conducted in August and November 2009. Several methods for determining the water column were employed, including radiosonde launches, continuous measurements by infrared radiometer, and VLT instruments operating at various wavelengths: CRIRES, UVES, VISIR and X-shooter. In a first for astronomical instruments all methods have been evaluated with respect to the radiosondes, the established standard in atmospheric research. Agreement between the radiosondes and the IR radiometer (IRMA) is excellent while all other astronomical methods covering a wavelength range from 700 - 20000 nm have also been successfully validated in a quantitative manner. All available observations were compared to satellite estimates of water vapour above the observatory in an attempt to ground-truth the satellite data. GOES can successfully be used for site evaluation in a purely statistical approach since agreement with the radiosondes is very good on average. For use as an operational tool at an observatory GOES data are much less suited because of significant deviations depending on atmospheric conditions. We propose to routinely monitor PWV at the VLT and to use it as an operational constraint to guide scheduling of IR observations at Paranal. For the E-ELT we find that a stand-alone high time resolution PWV monitor will be essential for optimizing the scientific output.

Proceedings Article | 11 July 2008 Paper

Comparison of precipitable water vapour measurements made with an optical echelle spectrograph and an infrared radiometer at Las Campanas Observatory

Richard Querel, David Naylor, Joanna Thomas-Osip, Gabriel Prieto, Andrew McWilliam

Proceedings Volume 7014, 701457 (2008) https://doi.org/10.1117/12.789365

KEYWORDS: Atmospheric modeling, Lanthanum, Data modeling, Observatories, Infrared radiation, Absorption, Radiometry, Spectrographs, Radio optics, Infrared astronomy

Read Abstract +

Showing 5 of 10 publications

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years